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Brucellosis is a world prevalent endemic illness that is transmitted from domestic animals to humans. Brucella spp. exploits urease for survival in the harsh conditions of stomach during the gastrointestinal infection. In this study, we examined the immune response and the protection elicited by using recombinant Brucella urease (rUrease) vaccination in BALB/c mice. The urease gene was cloned in pET28a and the resulting recombinant protein was employed as subunit vaccine. Recombinant protein was administered subcutaneously and intraperitoneally. Dosage reduction was observed with subcutaneous (SC) vaccination when compared with intraperitoneal (IP) vaccination. rUrease induced mixed Th1–Th2 immune responses with high titers of specific IgG1 and IgG2a. In lymphocyte proliferation assay, splenocytes from IP and SC‐vaccinated mice displayed a strong recall proliferative response with high amounts of IL‐4, IL‐12 and IFN‐γ production. Vaccinated mice were challenged with virulent Brucella melitensis, B. abortus and B. suis. The SC vaccination route exhibited a higher degree of protection than IP vaccination (p value ≤ 0.05). Altogether, our results indicated that rUrease could be a useful antigen candidate for the development of subunit vaccines against brucellosis.  相似文献   
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AIMS: To assess the relationship between neighbourhood deprivation and the rate of gestational diabetes mellitus (GDM) using routinely collected data from a clinical information system, in Plymouth, UK. METHODS: Between 1 January 1996 and 31 December 1997, 3933 women residing within the Plymouth Primary Care Trust (PCT) were screened for GDM using indices of neighbourhood deprivation and prevalence of GDM. Areas (n = 43) were classified according to the Townsend index, measuring material deprivation. Pregnant women with and without GDM were compared. RESULTS: The prevalence of GDM was 1.7%[95%, confidence interval (CI) 1.20, 2.11]. The prevalence of GDM ranged from 1.05% (95% CI 0.60, 1.70) in the most deprived to 2.10% (95%, CI 1.34, 3.13), in the least deprived neighbourhood. Crude rates decreased by 50%[relative prevalence (RP) (95% CI) 0.50 (0.27, 0.94); P = 0.06] amongst those living in the most-deprived compared with those living in the least-deprived areas. Using a stepwise binary logistic regression model, older age at delivery significantly increased the risk of developing GDM. [RP (95%, CI) 1.09, (1.04, 1.13)]. Townsend deprivation score had no significant independent association with GDM when other covariates were considered. CONCLUSION: These data suggest that the neighbourhood context in which women live has no impact on the risk of GDM. Diabet.  相似文献   
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Objective: To mechanically test the intact cardiac structure to determine the sequence of contraction within the myocardial mass to try to explain ejection and suction. Methods: In 24 pigs (30–85 kg), segment shortening at the site of sonomicrometer crystals was continuously recorded. The ECG evaluated rhythm, and Millar pressure transducers measured intraventricular pressure and dP/dt. Results: Study of segment shortening defined a sequence of contraction within the myocardial mass, starting at the free wall of the right ventricle and on the endocardial side of the antero-septal wall of the left. Crystal location defined underlying contractile trajectory; transverse in right ventricle followed by basal posterior left ventricle, and from the endocardial anterior wall to the posterior apical segment and finally to the epicardial side of the anterior wall. Mean shortening fraction averaged 18±3%, with endocardial exceeding epicardial shortening by 5±1%. Epicardial segment crystal displacement followed endocardial shortening by 82±23 ms in the anterior wall, and finished 92±33 ms after endocardial shortening stopped, time frame that matches the interval of fast drop of ventricular pressure and the start of suction. Conclusions: Crystal shortening fraction sequence followed the rope-like myocardial band model to contradict traditional thinking, with two starting points of excitation–contraction, the right anterior free wall of the right ventricle, and the endocardial side of the anterior wall. Active suction may be due to active shortening of the epicardial fibers of the anterior wall, because relaxation was not detected when both mitral and aortic valves were closed during the interval previously termed ‘isovolumetric relaxation’.  相似文献   
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The purpose of this study was to explore the fate of a single dose of labeled selenium as determined by its route of administration. Thus, the appearance of a stable isotope of selenium, administered as 74-Se-selenite, was measured in plasma, urine, and feces, with neutron activation analysis, following a 81.7 micrograms dose of 74Se-selenite given either intravenously or orally in two groups (n = 4) of healthy, young adult men, who were otherwise maintained on a diet providing a constant and adequate selenium intake. From these isotopic data, measurable parameters of urine excretion, total body retention and selenite-exchangeable metabolic pool (Se-EMP) were defined to provide a quantitative assessment of selenium metabolism in these subjects. The initial 24-hr urine excretion of the label was higher for the intravenously administered label (18.2 +/- 2.1% of dose) compared to the oral dose (11.7 +/- 2.6% absorbed dose). Thereafter, the excretion of isotope was the same for both groups. For equivalent entry of Se into the body, measured total body retention and Se-EMP were the same for both groups. These initial kinetic data suggest that the overall utilization of selenium from a single administration of selenite is comparable for the two routes of intake and that the host's selenium requirement can probably be met adequately via the intravenous administration of selenite.  相似文献   
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We examined the effect of chronic selenite supplementation on whole body and selected organ selenium (Se) accumulation, urine excretion of total Se and trimethylselenonium ion, and Se balance in adult male rats. Animals were housed in metabolic cages and given either deionized water or water containing 4 micrograms of Se/mL as selenite for 30 d. Absorption of selenite was nearly complete, with only approximately 10% of ingested Se appearing in feces. There was a rapid rise in urinary Se that reached a plateau within a few days and accounted for 54 +/- 2% of the intake. Excretion of trimethylselenonium ion (TMSe) in urine increased rapidly, representing 35-40% of urinary Se in the supplemented animals compared with only 2% for the control group. In one experiment, rats were killed at 30 d and total carcass Se was measured using isotope dilution analysis. Supplemented rats had only a modest increase in whole body Se (94 +/- 4 micrograms Se vs. 66 +/- 3 in controls). Calculation of Se balance in the supplemented rats showed that approximately 35% of ingested Se could not be accounted for by urine plus fecal losses combined with the portion retained in the carcass. The results from this study demonstrate that under the condition of supplementation at 4 micrograms of Se/mL of drinking water, pathways other than urinary and fecal excretion may account for a substantial portion of Se loss.  相似文献   
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The interaction between dietary ascorbic acid at extremes of ascorbic acid intake and selenium in young adult male humans was investigated with a stable-isotope approach using 74Se-selenite. Measurements were made of 74Se in plasma, urine, and feces with neutron-activation analysis after oral administration of 74SeO3(2-). Urine excretion and total body retention of isotope and the selenite-exchangeable metabolic pool (Se-EMP) were calculated. Limiting dietary ascorbic acid to about 20 mg/d appeared to reduce the time-related retention of absorbed selenite and the size of Se-EMP. Compared with a diet providing 1 g ascorbic acid/d the low ascorbic acid intake was associated with a lower fractional absorption of the isotope, a reduced retention of the label, and a smaller Se-EMP. These data and those previously obtained in subjects with more usual ascorbic acid intakes point to a possible important role for ascorbic acid in the maintenance of Se homeostasis.  相似文献   
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BackgroundIntraoperative tourniquet use in total knee arthroplasty (TKA) is a common practice which may improve visualization of the surgical field and reduce blood loss. However, the safety and efficacy associated with tourniquet use continues to be a subject of debate among orthopedic surgeons. The primary purpose of this study is to evaluate the effects of tourniquet use on pain and opioid consumption after TKA.MethodsThis is a multicenter randomized controlled trial among patients undergoing TKA. Patients were preoperatively randomized to undergo TKA with or without the use of an intraoperative tourniquet. Frequency distributions, means, and standard deviations were used to describe baseline patient demographics (age, gender, race, body mass index, smoking status), length of stay, surgical factors, visual analog scale pain scores, and opioid consumption in morphine milligram equivalents.ResultsA total of 327 patients were included in this study, with 166 patients undergoing TKA without a tourniquet and 161 patients with a tourniquet. A statistically significant difference was found in surgical time (97.87 vs 92.98 minutes; P = .05), whereas none was found for length of stay (1.73 vs 1.70 days; P = .87), postop visual analog scale pain scores (1.73 vs 1.70; P = .87), inpatient opioid consumption (19.84 vs 19.27 morphine milligram equivalents; P = .74), or outpatient opioid consumption between the tourniquet-less and tourniquet cohorts, respectively. There were no readmissions in either cohort during the 90-day episode of care.ConclusionUtilization of a tourniquet during TKA has minimal impact on postoperative pain scores and opioid consumption when compared with patients who underwent TKA without a tourniquet.  相似文献   
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